In mobile wireless communications, for example, data may be transmitted between a service provider and a mobile telephone over a mobile wireless network, e.g., to load Internet email from the service provider into the mobile telephone. For example, a mobile wireless system according to the GSM standard (Global System for Mobile Communications) described in the publication “GSM Global System for Mobile Communication” J. Eberspacher, H. J. Vögel, B. G. Teubner, Stuttgart, 1997, wherein data to be transmitted over the mobile wireless network may be encrypted in a corresponding encryption unit and thus may be protected from unauthorized access. According to the GSM standard, the key with which the data to be transmitted is encrypted may be established by the mobile wireless system and thus by the network operator. Control of this key thus may lie with the network operator with which the mobile telephone is registered. The user may thus be unable to use the mobile telephone encryption functionality available in the mobile telephone independently of the network operator.
In addition, as described in the publication “Radio Interface Protocol Architecture,” 3GPP TSG RAN WG2, TS25.301 v. 3.1.0, 1999, the encryption unit of the mobile telephone may be used to encrypt a device identifier of the mobile telephone and thus protect it from unauthorized access during its transmission to the mobile wireless network. However, this device identifier may be predetermined by the manufacturer of the mobile telephone. The user of the mobile telephone may thus be also unable to use the encryption functionality available in the mobile telephone independently of the manufacturer of the mobile telephone.